The present invention relates generally to information record carriers using optical means and drives for driving the same, and more particularly to an information record carrier that stores user data for use with a user and controls an access to the user data and a drive for driving the same. The present invention is directed, for example, to an optical disc that records video information, voice information, text information, software, and the like and stores a security code used to access the optical disc, and a drive for driving the same.
In general, an optical disc divides an area into a lead-in area, a (user) data area, and a lead-out data. The lead-in area, located outside the user data area and provided at a side from which the disc is first accessed, includes a control area. The lead-out area is a buffer area indicative of an end of reading, and provided at the innermost or outermost circumference opposite to the lead-in area. The lead-in and lead-out areas are those which a user does not access, and typically store control information and test information. On the other hand, the data area is those which a user may utilize, and a recordable and reproducible disc uses this area to store information (or user data). The control area and data area are addressed in a similar manner, and an optical head may access both areas relying upon the address. In addition, the lead-in, lead-out and user data areas are generally recorded in the same recording manner.
Recordable and reproducible optical discs are subject to falsification and deletion of their recorded contents, and the stable preservation of recorded contents would be difficult. It is also undesirable that an unauthorized person accesses and leaks out recorded information in a recordable and reproducible optical disc. However, the mere prevention of unauthorized copying, as in Japanese Laid-Open Patent Application No. 10-199032, is an insufficient solution for this problem. On the other hand, Japanese Laid-Open Patent Application No. 8-147704 suggests that security data other than primary data (or user data) be recorded in a wobbling area for security purposes. Although this reference as an example uses second modulation (or wobbling) means as data superimposing means to store security data in addition to the primary data in the user data area, the disclosure appears to suppose a non-rewritable optical disc.
Thus, heretofore, no inexpensive and effective method have been proposed to preserve recorded contents of a recordable and reproducible, preferably standardized, optical disc, as well as to restrict an access to the disc so as to maintain recorded contents"" security. Therefore, current rewritable optical discs are in a defenseless state and it is currently difficult to restrict an access to an optical disc and to preserve an originality of its recorded contents.
For example, a conventional method for making an optical disc non-writable may maintain a stable preservation, but cannot prevent a leakage of recorded contents. In addition, when an optical disc is not standardized, the security would undesirably lead to a complicated and expensive system. For instance, as seen in standardized and commercialized products like certain medical-use optical discs, a partial modification of a standardized optical disc would maintain the security but lead to a special, complicated and expensive system architecture.
In order to solve the above disadvantages, it is an exemplified object of the present invention to provide an optical disc with secure ID data for control over recording and reproducing of the optical disc, and thereby to inexpensively achieve the stable preservation and security maintenance of recorded contents.
In order to achieve the above object, a recordable and reproducible optical disc of one aspect of the present invention includes a user data area and a control area which are continuously and integrally arranged, wherein each record area in the user data and control areas is divided along a circumference, each unit of the divided circumference is addressed, and each addressed unit is divided into a plurality of data lines so that the optical disc may be recorded, and wherein control data including error-detectable code data and ID data is recorded at least part of data lines in the control area having an address among addresses in the circumferential record areas. According to this optical disc, the control data is recorded partially or entirely in the control area and, in any event, is not necessarily recorded in the entire circumference on the disc. In addition, the control data stores only data amount corresponding to a narrow record area.
A recording method of another aspect of the present invention for a recordable and reproducible optical disc includes a user data area and a control area which are continuously and integrally arranged, wherein each record area in the user data and control areas is divided along a circumference, each unit of the divided circumference is addressed, and each addressed unit is divided into a plurality of data lines so that the optical disc may be recorded, the method including a step of recording data in part of the control area using a synchronous pattern having a minimum basic period different from a minimum basic period used for a synchronous pattern for reproducing data divided and recorded in the data lines. This recording method employs synchronous patterns using two types of minimum basic periods.
An optical disc drive of still another aspect of the present invention for driving a recordable and reproducible optical disc includes a user data area and a control area which are continuously and integrally arranged, wherein each record area in the user data and control areas is divided along a circumference, each unit of the divided circumference is addressed, and each addressed unit is divided into a plurality of data lines so that the optical disc may be recorded, and wherein control data including error-detectable code data is recorded at least part of circumferentially discontinuous and divided data lines in the control area having an address among addresses in the circumferential record areas, includes an optical pick-up for reproducing the optical disc, a signal processor, connected to the optical pick-up, for processing an output from the optical pick-up, a memory for storing a security program and security data relating to information on control data, and a controller for operating in accordance with the security program, and allows the optical pick-up and signal processor to record and reproduce the user data when the control data reproduced by the optical pick-up accords with the security data and when no error is detected during a reproduction action. This optical disc drive is compatible with the above optical disc.
Other objects and further features of the present invention will become readily apparent from the following description of preferred embodiments with reference to accompanying drawings.